So lets set aside the question of communication skills for the moment (because they're way to vague a concept, and if we develop communication in terms of strategies and tactics instead, "skills" probably amount to knowing when and how to deploy a given strategy/tactic anyway), and let's suppose that overarching communication strategies exist in general. Let's suppose, for instance, that one can very often settle on a strategy of "Knowledge > Application > Analysis > Evaluation" for at least problem-solving communications (of which, a shit ton of communication is anyway - an academic paper is a problem-solution setup, any test question, any political discussion, any discussion requiring an outcome, almost any discussion anywhere, right?)
So I think it's probably possible to speak of at least some kinds of communication in terms of the cognitive or personal skills that need to be deployed in the service of that communication. Maybe (wild hypothesis) all communication strategies can, at a sufficiently general level, be described in such terms. In that case, communication tactics amount to maneuvers meant to further the adequate deployment of a given skill. "Knowledge" for instance if understood as a skill, noting that the skill of knowledge lies in how and when knowledge is wielded, is brought into any communication by such tactics as "You know what, let's check that in the textbook".
What I want to say though, that's the only "tactic" that's come to mind. There must be other general tips you can give to students on what to do when in need of some Knowledge within a communication, or some Application or some Whatever, right? There must be a collection of tactical moves any class of students can be introduced to that they would be expected to deploy from time to time in class discussion, and which they might come to rely on in keeping themselves using English.
Right?
Right.